AC自动机模板

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在一个字符串中出现模板串的个数

#include <iostream>
#include <string.h>
#include <stdio.h>
#include <algorithm>
#include <queue>
#include <math.h>
#define MOD 1000000007

using namespace std;
const int N = 1e6+10;
const int M = 26;
struct Trie{
int next
[M],end
,fail
;
int root,L;
int newNode(){
for(int i = 0; i < M; ++i){
next[L][i] = -1;
}
end[L++] = 0;
return L-1;
}
void init(){
L = 0;
root = newNode();
}
void insert(char buf[]){
int now = root;
for(int i = 0; buf[i]; ++i){
int x = buf[i]-'a';
if(next[now][x] == -1)
next[now][x] = newNode();
now = next[now][x];
}
end[now]++;
}
void build(){
queue<int>Q;
fail[root] = root;
for(int i = 0; i < M; ++i){
if(next[root][i] == -1)
next[root][i] = root;
else{
fail[next[root][i]] = root;
Q.push(next[root][i]);
}
}
while(!Q.empty()){
int now = Q.front();
Q.pop();
for(int i = 0; i < M; ++i){
if(next[now][i] == -1)
next[now][i] = next[fail[now]][i];
else{
fail[next[now][i]] = next[fail[now]][i];
Q.push(next[now][i]);
}
}
}
}
int query(char buf[]){
int now = root;
int res = 0;
for(int i = 0; buf[i]; ++i){
now = next[now][buf[i]-'a'];
int temp = now;
while(temp != root){
res += end[temp];
end[temp] = 0;
temp = fail[temp];
}
}
return res;
}
};
char buf
;
Trie ac;
int main()
{
int T;
int n;
scanf("%d",&T);
while(T--){
scanf("%d",&n);
ac.init();
for(int i = 0; i < n; ++i){
scanf("%s",buf);
ac.insert(buf);
}
ac.build();
scanf("%s",buf);
printf("%d\n",ac.query(buf));
}
return 0;
}